Wednesday, June 01, 2016

Can social science yield objective knowledge?

I've been having a fairly epic email argument with a lefty* social scientist friend, about whether social science can give us objective knowledge about the world. Apparently, it has become accepted in lefty* social science and humanities circles that the study of human beings is an inherently subjective enterprise, and will never yield the kind of knowledge delivered by physics, chemistry, biology, etc.

There are essentially three arguments for this. Paraphrasing heavily:

1) Social science has policy implications, and so ideological bias will always leak in, affecting both researchers' methodological choices and their interpretations of conclusions.

2) Social phenomena are highly complex, and hence can never be understood in the way natural phenomena can be.

3) Social science = humans studying other humans, and "reflexivity" prevents us from understanding ourselves in the same way we could understand the behavior of ants or atoms.

I think all that each of these arguments highlights an important difficulty of doing social science, but gets the implications wrong.

In fact, in recent decades, a few very successful predictive social science theories have emerged that don't suffer much from any of these problems. My four favorite examples are auction theory, gravity models, matching theory, and random-utility discrete choice models. Each of these is not just very predictive, but very useful to humanity. They power Google auctions, allow people to forecast trade flows, improve organ transplants, let cities predict how many people will use the train, and allow humanity to do many other things.

Keeping these examples in mind, let's go through the (heavily paraphrased) arguments one by one.**

1) First, the presence of ideological bias. Yes, these days few people care about the policy implications of the orbit of Venus, while most people care about the policy implications of minimum wage studies. So these days, people are more likely to be objective about the former than the latter. But it was not always thus! There was a time when scientists were being put under house arrest (or worse) for saying politically incorrect things about the orbits of the planets.

Eventually, the facts won out. Natural scientists who ignored the prevailing ideology were able to predict the motion of the planets better than their rivals, and that basically settled it. There seems no reason, in principle, why a similar process wouldn't happen with social science.

Now, it might happen a lot slower, because really super-predictive social science theories are harder to get than super-predictive physics theories. But predictive success seems to drive out ideology, meaning that social science has a chance of being objective.

Some people think it's a good idea for social science researchers to lay their cards on the table - to admit their ideologies when they report their research results. That sounds like a nice idea, but I suspect it is not even slightly feasible in practice. Imagine an economist saying "From this natural experiment, I find the elasticity of labor supply with respect to minimum wage increases to be -0.1. Also, you should know I'm a lefty type who wants to use policy to help the working class."

Well, how much did the economist let said ideology affect said estimation? Did he underestimate the elasticity because he thinks that reporting a small number will make people more likely to enact minimum wages, which he thinks will help the working class? Did he overestimate the elasticity in a conscious or unconscious attempt to correct for his bias? Did he try to get an unbiased estimate, because he doesn't know whether minimum wage would help or hurt the working class, and he wants to find out?

Who knows??? Not him. Not the reader. So this sounds like a nice idea, but I don't think it would work in practice at all. In practice it would just lead to a lot of confusion, suspicion, and noise.

2) Second, complexity. Well, again, this is a big challenge in natural sciences too! Quantum mechanics and relativity have passed every empirical test, to arbitrary levels of precision. But will these things tell us how a tree grows? Maybe. But if so, that's certainly far in the future. Right now, there are plenty of phenomena too complex for particle physics to understand. That doesn't mean particle physics is incapable of yielding objective knowledge.

To me, the argument that social science phenomena are too complex seems quite a bit like the "irreducible complexity" that creationists use to argue for "intelligent design". Yes, you can always find some phenomenon so complex that existing theories can't (yet) explain it. And as theories get better and better, you can keep on jumping up to even more complex theories, saying "Oh yeah? Explain that, scientists!".But that just means you keep losing and losing, as scientists get better and better at explaining the world.

I guess you can jump directly to the most complex, hard-to-study phenomena of all - macroeconomics, politics, and history - and camp out there for a good long while, constantly saying "See? Told you so! You haven't explained this stuff yet, and you never will!" And you're probably safe - you'll be in your grave before science explains these hellishly complex, probably-non-ergodic macro-phenomena.

Well, good for you! But in the meantime, the sphere of things that can be explained by science will expand...

3) "Reflexivity". The idea that humans can't study their own behavior. If you manage to make a theory that predicts human behavior, people's behavior will change so that the theory no longer works.

Well that's obviously wrong. Here's a very useful, robust law of human behavior that many humans have rediscovered over the years: if you walk up and threaten random humans with a deadly weapon, they'll probably hand over their money.

But there are obviously lots of situations in which it probably doesn't come into play very much. Epidemiologists figured out that when everyone washes their hands, disease has more difficulty spreading. So they made rules and public awareness campaigns trying to get people to wash their hands. The rules and campaigns worked, and now disease has a harder time spreading in rich countries. Reflexivity be damned! There are also plenty of examples in econ - the response to taxation, for instance, or the labor market effects of immigration - that have no obvious reflexivity problem.

So while ideology, complexity, and reflexivity are real challenges in social science, they don't seem insurmountable. They don't seem to represent a fundamental difference between social and natural science.

These arguments against objective social science really feel a lot like the "God of the gaps" reasoning that religious thinkers use to argue against the universality of natural science. Every gap in science's current ability to explain the world is presented as a reason to embrace religion - usually the specific religion of the person making the argument.

When it comes to social science, the "natural alternative" for the people making the above arguments isn't God, it's lefty* ideology. Into every gap in our current understanding of social phenomena should flow the conviction that the have-nots are oppressed by the power of the haves. Arguing with lefty* friends in the soft-sociology/anthropology/humanities complex feels a bit like arguing with a Catholic priest about science back in 1700. "You can predict balls rolling down ramps, but can you tell me when the next thunderstorm is going to happen? No you can't! See? Nature is inherently mysterious! Only the Bible will show you the truth!"

Social science is damn hard (and not just for the reasons described above). It'll be many years before predictive social theories get good enough to understand things like recessions, elections, or the rise and fall of great powers. Maybe it'll never happen. But that's not a reason to give in to ideological, desire-based worldviews. We should keep crawling forward toward a better and better objective understanding of the world.

*"Lefty" is not meant as a pejorative here. I just don't have a word for the Marxist-influenced, left-leaning idea/ideology package that has become dominant in the humanities and soft social sciences, along with the methodology of critical theory. It is a very broad, complex, multi-faceted idea/ideology package with no commonly accepted over-arching name, so "lefty" will have to do for now. If you know a better term, let me know.**Obviously this is a one-sided exercise, since I'm responding to my own summaries/paraphrasing of the opposite side. But that doesn't mean it's a straw man. The concepts and ideas I put forth will be summarized and paraphrased in your own mind, and next time you encounter someone who says something kinda-sorta like the arguments I describe, you can use your internally summarized and paraphrased arguments to think about the filtered, summarized, paraphrased versions of that other person's arguments that appears in your own mind. The purpose here is to present ideas, not to definitively win an argument or settle a point.

Part of what you're getting at (I think, or hope) is that, if we can't explain everything, we at least have a good idea why it's going to be hard to explain everything. "Reflexivity" is an example - why regularities in the data may not tell you anything useful.

In any case, I think economics is fascinating. I'd rather do this than come into the lab every day and check on the mice.

Checking on the mice is what grad students are for! Then the grad students come and report what they find, and you add a hand-wavey theory, and they write up the paper! Then when they've done that for a few years, and a few more years of postdoc, you write a letter to a friend at another university and tell them to hire your grad student as a prof, and they do! Then the system repeats. Meanwhile, you spend most of your time writing grant proposals. This is my impression of how lab science works... :-)

I entered 'anthropology' in the above search function and came up with a blank. There, as you know, the battle rages. I find evolutionary studies on ethics, religion, and various aspects of cognition enlightening. I would be interested in your thoughts.

My skepticism - having hung around anthropologists for a while - is just that human culture tends to be a lot more diverse than people think it is.

When we see someone do a study of a few tens of students at a midwestern US state university and generalize that into a universal law of human behaviour, we're rightly skeptical. Aside from any statistical issues, you have to ask, is a bunch of university students a reasonable sample of human behaviour.

More generally in the social sciences when can we believe that we have a "good enough" sample of the complete gamut of human behaviour to draw conclusions from our sample and state that we are objectively describing human behaviour itself and not some changeable artifacts of western culture in the early 21st century?

The notion that the Earth is not atypical in the universe probably works in physics and isn't a bad philosophical assumption. But the social science equivalent - that the world today is a "typical" world in that we can safely generalize from what we see in front of us to more universal truths about human behaviour - that's a lot more fragile and often pretty hopeless.

This falls under his non-ergodic caveat the makes things hard. The whole problem with a non-ergodic process or phenomena is that the time scale over which it can be characterized will never be sufficient to smooth out stochastic variations. Basically the problem will always be subject to the critique of sample size.

Those theories are correct... it's just that in practice, they don't often matter or can be overcome.

Philosophy often does extended thought experiments that illustrate something novel or how threadbare some of our notions are. Like Hume and causality. Like Berkeley and his curious idealism.

But no one lives doubting causality. No one lives thinking everything is an illusion that God has implanted in our heads (although Berkeley really might have done so).

Those three points in social science are, strictly speaking, correct. There's plenty of philosophy that tells you why they're correct.

And there's plenty of irrefutable philosophy that concludes causality is not quite what it seems. But so what? We don't need irrefutable proof: we need efficacy. Does something work? If so, continue, and leave the theory to philosophy.

I would agree that the relfex of the victim in handing over the money is stronger than the reflex they have in response to a social scientist studying their behavior. The gun has a much stronger impact on determining reality than a social scientist studying the situation. The act of agents studying things can often cause a reflex but other things are often much stronger.

"[I]f you walk up and threaten random humans with a deadly weapon, they'll probably hand over their money."

I'm glad that somebody is finally fighting against the historically uniformed and simply untrue "An armed society is a polite society." nonsense. Have these people read about lawless armed societies, such as Afghanistan under the jirgas? Even today, people who are stuck up by thieves in backwoods China can easily scare them off if they don't mind the fact that their friends will take revenge. Hell, try watching The Wire and look for a correlation between armament and such things.

This is a great regularity in all of human history and I'm glad you brought it up. Pinker's work on the history of violence - mostly known for his finding about its scale and not his more interesting finding about its distribution - is a good example of social science (though I can see why you avoided such an unsettled field).

The key problem with social science is that the essential element you would need to understand to understand it would be a full understanding of the human brain. If you study behavior, you're really just looking at symptoms, not the root cause of social behavior - and thus it would be highly variable on not objective - totally unlike what causes the orbits of planets.

Human behavior is the result of brain activity, and we have little knowledge of how the brain really operates.

Yes, it is useful to study human behavior, but we're dealing with approximations, not objective truth. And this article confirms that there is bias, and not just ideological - social scientists have bias that social science can be objective.

Otherwise they would call it social studies. And that's what it should be called.

You can't even get past first base without exhibiting reflexive behaviour. Why the need to report that this post is the result of discussions with a leftie friend? Ironic, no?

The natural sciences have been doing precision repetiting experiments for 300 years. Even when astronomy was called astrology, the position of heavenly bodies could be predicted with high accuracy merely based on the practice of previous observation - no fancy theories needed. Where can this be done in the social sciences? What is the record of the social sciences in the last 300 years?

Why not post-modern instead of lefty? Lefty works in a lot of cases, especially on academia, since academia is mostly lefty. But aren't there a lot of libertarians out there now who consider themselves righties who think every problem can be reduced to a government being too restrictive on individual liberty? Are these righties swayed by science any more than their lefty counterparts?

Why not post-modern instead of lefty? Lefty works in a lot of cases, especially on academia, since academia is mostly lefty. But aren't there a lot of libertarians out there now who consider themselves righties who think every problem can be reduced to a government being too restrictive on individual liberty? Are these righties swayed by science any more than their lefty counterparts?

Surely the subjectivity of social sciences is also rooted in the fact that we're deciding what we're studying and how we're studying it. A political scientist could ask, "why do revolutions happen?" and construct a project to answer that question. Or that same political scientist could ask, "why don't revolutions happen?" and construct a project to answer that question. Both would be about the same empirical content. And neither would be "objective" in the sense of the data being independent of the person asking the question. And that question is rooted in the fact that it is a human being (with experiences, understandings, dreams, aspirations, etc.) trying to understand different human beings.

And this example, while easy enough to come up with, is mirrored in all social science work. We simply ask the questions that we ask about humans because of who we are as humans.

But that lack of objectivity isn't grounds or justification for a lack of methodological rigor or a lack of theoretical coherence. It's not a post-modern relativism that should replace objectivity, but a clear-eyed understanding of the potential and limits of social science.

I, quite honestly, think that social scientists should spend a lot less time worrying about how we compare to the physical or natural sciences. It's not a comparison that will ever flatter us. We have a lot to offer in terms of understanding the human condition. Let's embrace that which we can know and learn and communicate, and stop pretending to be that which we cannot be.

A political scientist could ask, "why do revolutions happen?" and construct a project to answer that question. Or that same political scientist could ask, "why don't revolutions happen?" and construct a project to answer that question. Both would be about the same empirical content.

And both would eventually find the same answer (if any answer is to be found at all). In econ, these are thought of as the same question. "Why do recessions happen" and "Why don't recessions happen" are the exact same question, to my ears.

That's why, for social science at least, post-positivism is the most responsible epistemological way of looking at the world, because it takes into account of bias and perspectives of the researcher and of existing theory, while also trying to discover the "objective truth" as positivism does. Critical Theory / Post-structuralism / Post-modernism rejects an "objective" truth" with an idea that truth is relative. Thus it just of course be tossed out.https://en.wikipedia.org/wiki/Postpositivism

And also, while lefty* is true, the reverse is perfectly possible for righty*s and libertarians, what with Austrian economics and its methodological individualism.

"To me, the argument that social science phenomena are too complex seems quite a bit like the "irreducible complexity" that creationists use to argue for "intelligent design". "

If you understood the concept properly, irreducible complexity is a challenge that random Darwinian evolution cannot meet. Furthermore, intelligent design does not equal creationism. If you come to the conclusion that life is intelligently designed, that gives you no clue as to the identity of the designer.

The shorthand argument that failure to put your faith in RDE is just creationism is used by the lazy who don't want to come to grips with the real problems with the theory of evolution.

1) Remains important not just because of ideological biases but because of differences in meaning, understanding, and shared symbolic values.

2) Is not particularly relevant. Complexity is an issue and perhaps more of an issue than the physical sciences, but that does not prevent objective knowledge in itself.

3) Is obviously correct. If you walk up and threaten random humans with a deadly weapon, they'll probably hand over their money. The *first* time. If it becomes known that there are repeated experiments by field sociologists testing the proposition, people will say "Ha! You're probably just another field sociologist and not *really* threatening me with a weapon, but just *pretending* you are for the purposes of the experiment."